Safety control means with flash



Aug. 29, 1950 w. D. ANTRIM SAFETY conmox. MEANS WITH FLASH TUBE FOR OVENBURNERS Filed Aug. 1a, 1945 WILL/AM 0. fiwm/M Patented Aug. 29, 1950SAFETY CONTROL MEANS WITH FLASH TUBE F08 OVEN BURNERS William D. Antrim,Cleveland, Ohio, assignor, by

meme assignments, to Amliated uaa Equipment, 1nc., Uleveiand, Ohio, acorporation of Delaware Application August 18, 1945, Serial No. 611,356

2 Claims. (Cl. 158-1174) This invention relates to means forautomatically igniting the oven burner of a gas range from a constantlyburning pilot such as the pilot heretofore employed for ignition of thetop burners of the range. Briefly, the invention contemplates theemployment of a safety pilot immediately serving the oven burner, and aflash tube and pilot therefor efiective for ignition of the safety pilotfrom the top burner pilot.

The obJects of this invention are to provide a. control circuit for suchflash pilot. which circult may employ an improved flash tube and pilot.as will appear hereinafter.

Further objects and advantages will be apparent from the followingdescription taken in connection with the accompanying drawings in which:

Fig. 1 is a diagrammatic view illustrative of essential parts of a rangeembodying the invention;

Figs. 2 and 3 are enlarged details in elevation and typical section,respectively. of the flash tube and flash pilot burner or charging meansappearing in Fig. 1; and

Fig. 4 is an enlarged typical section of an embodiment of the valveemployed.

With reference now to the drawings, and flrst to Fig. 1 thereof, I isthe main burner located within the range oven as indicated by the brokenline 2, the burner being located and adapted for either baking orbroiling, or both, as the case may be.

The main burner gas supply is had from the manifold 3 by way of themanual valve means l, line 5, which includes thermostatic valve meanslb, safety valve 6 and line I.

The valve means 4 embodies a manual on and oi! control as bymanipulation of the handle lid. The valve means lb embodies athermostatic throttling control responsive to the oven temperature hadin the usual manner by a thermally responsive element 8 located withinthe oven and a transmission line 8a leading therefrom to the valvemeans. v,}lhe arrangement is such, as will be appreciated by onefamiliar with the art, that the manual valve means having the handle lais ahead of the thermostatic valve means controlled by the thermalelement 8 so that the operator may turn the handle la to full openposition and the thermostatic throttling effect of the valve lb willnevertheless follow, responsive to oven temperature.

The valve means l also controls the pilot line I, the line 9 having itsgas supply from the line I, but ahead of the thermostatic valve means lbso that the line 9 is independent of even temperature.

The pilot line 9 leads to a safety pilot burner III by way of. a mixingdevice Illa where it is desired to employ primary air, the-pilot Illbeing located to provide ignition to the main burner I.

Safety valve means is provided for control of the main burner gas supplyline, responsive to the safety pilot burner' H). Details of such safetyvalve means are not material to this invention, but as here shown itincludes a valve body 0 having a main gas inlet 5a and outlet 1a, avalve head lie for control of the outlet 1a and shown in closed positionrelative thereto in Fig. 4, an element H in thermal responsive relationto the pilot flame l0 and suitable mechanism for control of the valvehead 6:1 by the thermally responsive element Ii. In the drawing suchmechanism is of snap-acting characteristic in cluding a link 20 carryingthe valve 6a, a lever 2i, having connection with the thermallyresponsive element H, and a tension spring 22 eifective between the link20 and lever 2|. The link 20 is seated in a bridge 23 within the valvebody and the lever 2| is mounted in a sealing diaphragm 24.

The arrangement is such that the safety valve and associated parts willbe in closed position as illustrated Fig. 4 to cut oil gas supply to themain burner in the absence of operation of the safety pilot in, but whenthe thermally responsive element II is heated by operation of the safetypilot ID as indicated in Fig. l, the safety valve will open, moving itshead But to the left, Fig. 4, to permit gas flow to the main burner asindicated by the large arrows Fig. 4; such safety valve operation, bothon and ofi, being automatically responsive to operation of the safetypilot Ill.

The range is provided with a constantly burning pilot l2 here shown asfed directly from the manifold 3, and which may be the usual provisionfor ignition of the range top burners, as through flash tubes thereto,but not here illustrated.

What has thus far been described is generally old and well known in theart; and this invention provides flash tube means for igniting thesafety pilot burner Hi from the constant pilot burner 12, automaticallyupon opening. of the oven burner control valve means 4.

For such purpose an open ended flash tube I3 having a cooperative flashgas supply tube may be provided as here shown. As indicated in detail inFigs. 2 and 3, the flash tube 13 is of 3 porous open construction as ofwoven wire and isflexible for ease of installation; and the flash pilotburner or charging means it comprises a tube extending within the flashtube I3 and a substantial distance therealong and provided therewithinwith a number of small outlet ports Ila at intervals or spaced locationstherealong. It will be appreciated that the flash tube and pilot heredescribed may be, if preferred, of more conventional constructioncomprising the more usual rigid flash tube and single charging port orflash burner therefor.

The flash pilot burner i4 is served by a line I I which may include theadjusting valve l8 and which is controlled automatically from the piloti0, but subject to the pilot line 9 and consequently to the manual valve4 also, as follows: A connection i1 is provided leading from the pilotline 9 to the body of the automatic valve 0, by way of the inlet Ila.therein, the body hav ing an outlet l5a from which the line l5 hasconnection. A diaphragm I8 is so arranged in the valve body that itcontrols flow between the openings Illa and Ila, yet maintains boththese openings at all times without communication with either of theopenings 5a and la in the main burner gas line. The diaphragm I8 isunder the control of a head IS on the main valve proper 6a, thearrangement being such that when the valve 8 opens to the main burnerline 1, it closes to the flash pilot line i5 and vice versa, directionof flash pilot gas flow being indicated by small arrows in Fig. 4.

The valve means described, and herein illustrated in Figs. 1 and 4, andwhich is responsive to the safety pilot i0 through the action of thethermally responsive element H, is thus of dual nature with respect tothe main burner gas supply. It is a safety valve which automaticallypermits gas flow to the main burner, ony during safety pilot operation.As to the flash tube, however, by virtue of the diaphragm l8 and head I9, it admits energizing gas to the flash tube before admitting gas tothe main burner and automatically cuts off flash tube gas duringoperation of the main burner.

The operation will be as follows, commencing with the manual oven burnercontrol valve means in "of? position and only the constant pilot II! inoperation:

When the operator desires operation of the burner I, the manual valve tois simply turned to full on position, the desired thermostatic oventemperature setting having been made at the thermostatic valve 4b.

Opening of the manual valve means admits gas to the lines 5 and 9. Thethermostatic element if being cold, the valve 6 prevents flow to themain burner supply line I, but gas is admitted from the line 9 by way ofthe connection i1 past the valve 6, through the line I! to the ports Haof the flash pilot burner [4, thus releasing a small energizing volumeof gas within the flash tube l3 with distribution therealong. This gasmingles with the air within the flash tube to form a combustible mixturewhich is ignited by the constant pilot l2 and in turn ignite the safetypilot i0 which latter has been receiving gas from the line 9 sinceopening of the manual valve so that it has been purged of air.

Ignition of the safety pilot ll heats the thermal element i l which inturn shifts the valve 6 to cut of! gas supply to the flash pilot burnerand admit gas to the main burner I which is infmediately ignited fromthe safety pilot.

On safety pilot outage for anycause, cooling of the thermal element Hreturns the valve 0 to safety position, cutting of! gas to the mainburner and re-admitting gas to the flash pilot for automatic re-ignitionof the safety pilot from the constant pilot.

When the oven is brought up to predetermined temperature by the mainburner, the thermostatic valve means lb begins to throttle down the,main burner responsive to the thermal element 8. This, however, has noeffect upon the gas pressure in the line I so that the safety pilot [0continues in operation without impairment of its effect upon the thermalelement ll; nor, should recycling take place following outage of thesafety pilot, will there be any throttling effect upon the flash pilotburner. These are important advantages particularly as to the flash,which is necessarily somewhatcritical in many commercialinstallations.

I claim:

1. In a gasrange having a top pilot burner, an oven with a main burnertherein, a safety pilot arranged to serve said main burner, gas supplymeans for said oven burner including a safety valve means controlled bysaid safety pilot and manual valve means, and gas supply means for saidsafety pilot subject to said manual valve means: means providingignition for said safety pilot from said top pilot burner, .andincluding flash pilot burner means, flash tube means arranged to receivea gas charge from said flash pilot burner means, and have ignition ofsaid charge from said top pilot burner, and means providing gas supplyfor said flash pilot burner means from said safety pilot supply means,and including valve means responsive to said safety pilot, to cut offsaid flash pilot burner means upon safety pilot ignition, and to passgas to said flash pilot burner means upon safety pilot outage.

2. In a gas range having a top pilot burner, an oven with a main burnertherein, a safety pilot arranged to serve said main burner, gas supplymeans for said oven burner including a safety valve means controlled bysaid safety pilot and manual valve means, and gas supply means for saidsafety pilot subject to said manual valve means: means providingignition for said safety pilot from said top pilot burner, and includingflash pilot burnermeans, flash tube means arranged to receive a gascharge from said flash pilot burner means, and have ignition of saidcharge from said top pilot burner, and means providing gas supply forsaid flash pilot burner means, and including valve means responsive tosaid safety pilot, to cut of! said flash pilot burner means upon safetypilot ignition, and to pass gas to said flash pilot burner means uponsafety pilot outage.

WILLIAM D. ANTRIM.

REFERENCES CITED The following references are of record in the flle ofthis patent:

UNITED s'rs'ms Ps'rEN'rs Dobler Dec. 22, 1942 Certificate of CorrectionPatent No. 2,520,298 August 29, 1950 7 WILLIAM D. ANTRIM It is herebycertified that error appears in the printed specification of the abovenumbered patent requiring correction as follows:

Column 2, line 53, after the word tube insert 14; column 4,-lines 27 and47, after oven insert main;

and that the said Letters Patent should be read as-corrected above, sothat the same may conform to the record of the case in the PatentOfiice.

Signed and sealed this 28th day of November, A. D. 1950.

THOMAS F. MURPHY,

- Assistant aom/missioner of Patents.

